Developer Bethesda Softworks, has stated that Fallout 4 will run at a stable 30fps throughout all instances. The PC version of Fallout 4 will not be limited or locked to 30fps in any way though.
“Fallout 4 is 1080p & 30fps on Xbox One and PS4. Resolution and FPS are not limited in any way on the PC.”
Replying to a fan on Twitter Bethesda’s Pete Hines advised he’s pretty sure they hadn’t discussed it at all (in relation to rumours FPS would be locked on the PC version. It has also been recently confirmed that the title will entail Sony’s exclusive remote play feature, permitting all gamers whom own a PS Vita to transfer the title’s on screen gameplay to their handheld device.
You can compare the current screenshots between Fallout 3 and Fallout 4.
Fallout 4 will see gamers take to the 200 year old dilapidated remnants of post war Boston, in which players will be able to traverse the county’s vast and irradiated landscape, in order to obtain an array of vital new weapons and stifle their mutated adversaries.